orthopyroxene

/ (ˌɔːθəʊpaɪˈrɒksiːn) /

noun

a member of the pyroxene group of minerals having an orthorhombic crystal structure, such as enstatite and hypersthene

Scientific definitions for orthopyroxene

orthopyroxene
[ ôr′thə-pī-rŏksēn′ ]

Any variety of the mineral pyroxene that crystallizes in the orthorhombic system and contains no calcium and little or no aluminum. Enstatite is an orthopyroxene.